discourse/app/assets/javascripts/admin/addon/templates/customize.hbs

<AdminNav>
  {{#if this.currentUser.admin}}
    <NavItem
      @route="adminCustomizeThemes"
      @label="admin.customize.theme.title"
      @class="admin-customize-themes"
    />
    <NavItem
      @route="adminCustomize.colors"
      @label="admin.customize.colors.title"
      @class="admin-customize-colors"
    />
    <NavItem
      @route="adminSiteText"
      @label="admin.site_text.title"
      @class="admin-customize-site-text"
    />
    <NavItem
      @route="adminCustomizeEmailTemplates"
      @label="admin.customize.email_templates.title"
      @class="admin-customize-email-templates"
    />
    <NavItem
      @route="adminCustomizeEmailStyle"
      @label="admin.customize.email_style.title"
      @class="admin-customize-email-styles"
    />
    <NavItem
      @route="adminUserFields"
      @label="admin.user_fields.title"
      @class="admin-customize-user-fields"
    />
    <NavItem
      @route="adminEmojis"
      @label="admin.emoji.title"
      @class="admin-customize-emojis"
    />
    <NavItem
      @route="adminPermalinks"
      @label="admin.permalink.title"
      @class="admin-customize-permalinks"
    />
    <NavItem
      @route="adminEmbedding"
      @label="admin.embedding.title"
      @class="admin-customize-embedding"
    />
  {{/if}}
  <NavItem
    @route="adminWatchedWords"
    @label="admin.watched_words.title"
    @class="admin-customize-watched-words"
  />
</AdminNav>

<div class="admin-container">
  {{outlet}}
</div>